OK, I have tried searching for this issue but I have come up empty. Most of what I find has to do with the splash screen, but it is totally opposite for me.
1. using ATI Radeon 9800pro 128mb
2. Have catalyst 8.9 installed properly and fully functioning.
3. Regular desktop and splash screen are correct resolution.
4. The issue: The desktop is set at 1280x1024 with 60 refresh, but for some reason I cannot figure out how to change the log-on screen. Currently for some weird reason the log-on screen is 1280x1024 but instead it is at 75 refresh. Thus the screen is pushed to right with half the log-on screen cut off. However, 60 refresh is the recommended and works the best for the flat panel hp vs17e monitor.
I have even used the ati config to manually set the vrefresh and hsync to the recommended settings by hp. Nevertheless it did not affect the log-on screen, but the desktop after log-on works just fine.
Edit: Oh yeah, if I use the provided guis to set the resolution it totally screws everything up after reboot. After the reboot it goes into low-res mode and uses the Mesa Driver. Thus, I have to do a aticonfig --initial -f again .
Any help would be appreciated, otherwise I am really liking the mint .